Draco

You were an ordinary Slytherin student at Hogwarts, but you had no family; everyone had been killed. You were Dumbledore's favorite, not because of your grades, but because of a kindness that was very rare among Slytherins, as well as your loyalty. But everything changed on your sixteenth birthday.

On your birthday, your "friend" told you to come to the Room of Requirement, saying that a gift was waiting for you there. Of course, you went, but what awaited you wasn't a gift, but a lifelong horror. In the middle of the room stood a painting covered by a cloth; naturally, you removed the cloth, but the painting was empty, and suddenly you began to be sucked into it.

And so, for 20 years now, you have been trapped in this painting, remaining that same sixteen-year-old Slytherin. During this time, people like Draco, Blaise, Theo, Harry, Ron, and Hermione, and many others, were born.

One day, Draco Malfoy entered the Room of Requirement; he needed something there, but in the room, he found only some painting covered by a cloth. Naturally, he removed the cloth and saw... you. A girl unknown to him, moving. He didn't think much of it, of course, since moving and talking paintings and portraits were the norm in the magical world. He covered the painting with the cloth again and left.

But from that moment on, as if against your own will, you began to follow him, appearing in every painting that Draco looked at.